一起直流滤波器过负荷保护动作的分析及改进  

Analysis and Improvement of a DC Filter Overload Protection Action

作　　者：付琪 王永[1] 吴秀海 张磊[1] FU Qi;WANG Yong;WU Xiu-hai;ZHANG Lei(College of Electrical Engineering&New Energy,China Three Gorges University,Yichang Hubei 443002,China;UHV Converter Station Branch,State Grid Shanghai Municipal Electric Power Company,Shanghai 201413,China)

机构地区：[1]三峡大学电气与新能源学院,湖北宜昌443002 [2]国网上海市电力公司特高压换流站分公司,上海201413

出　　处：《计算机仿真》2024年第11期102-108,共7页Computer Simulation

基　　金：国网上海市电力公司科技项目(B3090V220001);国家自然科学基金资助项目(52007103);国网上海市电力公司科技项目(52090V230002)。

摘　　要：直流滤波器过负荷保护是保护直流滤波器中空心电抗器、电阻器免受过大的热应力而导致元件绝缘损坏甚至烧毁的重要措施。详细分析了实际工程中直流滤波器过负荷保护的算法原理,重点对反映空心电抗器的集肤效应和临近效应引起谐波电阻的变化的集肤效应滤波器以及因电磁式电流互感器测点不足需要配置的分流系数滤波器的设计原理进行了分析。针对某工程直流滤波器电阻器过负荷保护误动作的实例,提出一种可以避免直流滤波器电阻器过负荷保护误动的电磁式电流互感器配置方案,并直接比较电阻器支路电流有效值和保护定值大小关系作为过负荷保护的判据。经实际暂态故障波形和单步块方法联合进行仿真分析,仿真结果表明,相比于传统的隐式梯形数值积分方法,单步块方法可有效地抑制数值振荡现象,新保护方案可以避免直流滤波器内部接地故障对电阻器过负荷保护造成的影响,具有一定的工程应用价值。The DC filter overload protection is an important way to protect the hollow core reactor and resistor of the DC filter from excessive thermal stress,which may cause insulation damage or even burn out of the components.In this paper,the algorithm principle of DC filter overload protection in the actual project is analyzed in detail,focusing on the skin effect filter that reflects the skin effect of the air-core reactor and the design principle of the skin effect filter which causes the change of harmonic resistance due to proximity effect and the shunt coefficient filter which needs to be configured due to the lack of measuring points of the electromagnetic current transformer.Aiming at an example of the malfunction of the overload protection of the DC filter in the actual project,a current transformer con-figuration scheme that can avoid the malfunction of the overload protection of the DC filter is proposed,and the rela-tionship between the effective value of resistor branch current and the protection setting value is directly compared as the criterion of overload protection.Based on actual transient fault waveforms and combined simulation analysis using the single-step block method,the simulation results show that compared with the traditional implicit trapezoidal nu-merical integration method,the single-step block method can effectively suppress numerical oscillations.The new pro-tection scheme can avoid the impact of internal grounding faults of the DC filter on the overload protection of resistors and has practical engineering application value.

关 键 词：直流滤波器 过负荷保护 临近效应 故障仿真 

分 类 号：TM743[电气工程—电力系统及自动化]